This is the Script I used: :loop UARTInit(0, 0, 9600) #initialize UART0 UARTWrite(0, 0, 0x30) sleep(100) UARTWrite(0, 0, 0x31, "Hello UART-zero") UARTWrite(0, 0, 0x32, "Second Hello") sleep(100)

UARTInit(0, 1, 9600) #initialize UART1 UARTWrite(0, 1, 0x30) sleep(100) UARTWrite(0, 1, 0x31, "Hello UART-one") UARTWrite(0, 1, 0x32, "Second Hello") sleep(100)

UARTInit(0, 2, 9600) #initialize UART2 UARTWrite(0, 2, 0x30) sleep(100) UARTWrite(0, 2, 0x31, "Hello UART-two") UARTWrite(0, 2, 0x32, "Second Hello") sleep(100) Goto (loop)

Sounds like your wire has a loose connection or is broken. Try a new wire and secure it better on both ends.

Long as your arduino and ezb are set to 9600, there shouldn’t be a problem.

Also, post the arduino code.

It's not the wire. I added an extra wire via a breadboard to measure the voltage (I should use an oscilloscope but I don't have one) and noticed the changed behavior. I changed the wire nevertheless but problem is the same. Arduino Nano is on a breadboard EZ-Bv4 is connected with 3 wires originating from UART0 TX (first pin), D5 and D18 I use an extra wire to connect the Nano RX with one of the EZ-B wires

/* I2C LCD 16x2 Arduino Tutorial

• More info http://www.ardumotive.com/i2clcd(en).html
• Dev: Michalis Vasilakis Date: 19/11/2016 Ver. 1.0 */

//Libraries #include <Wire.h>
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd (0x27, 16, 2); // Set the LCD I2C address, if it's not working try 0x27. //LiquidCrystal_I2C lcd (0x27, 20, 4); // Set the LCD I2C address (20 chars 4 lines), if it's not working try 0x27.

void setup(){ Serial.begin (9600);

lcd.init(); // iInit the LCD for 16 chars 2 lines // lcd.init(); // iInit the LCD for 20 chars 4 lines lcd.backlight(); // Turn on the backligt (try lcd.noBaklight() to turn it off (mind CAPITALS!!!) // lcd.noBacklight(); lcd.setCursor(0,0); //First line lcd.print("EZ-B4 LCD Display"); lcd.setCursor(0,1); //Second line lcd.print("Ardumotive.com");

}

void loop(){ ReadInputFromPC (); }

void ReadInputFromPC () { if (Serial.available ()) { delay (100); while (Serial.available () > 0) { int temp = Serial.read();

  Serial.print ("Debug ");
  Serial.println (temp); 

  if (temp == 48) {
    lcd.clear ();
  }
  else {
    if (temp == 49) {
      lcd.setCursor (0,0);
    }
    else {
      if (temp == 50) {
        lcd.setCursor (0,1);
      }
      else{ 
        if (temp != 10) {
          lcd.write(temp);
        }
      }
    }
  }
}     

}
}

The delay after reading on the Nano means you're skipping/missing bytes from the transmitter (EZ-B)

Quote:

[font=OpenSans, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"]if (Serial.available ()) { [font=OpenSans, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"]delay (100); <--- THIS IS BAD [font=OpenSans, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"]while (Serial.available () > 0) { [font=OpenSans, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"]int temp = Serial.read();

[/font][/font][/font][/font]

Also, you're writing to the LCD between character reads from the UART. That's going to cause a delay while the write occurs - which will also result in missing characters.  Also, you're DEBUG.WRITE() which is sending data out of a UART and that's gonna be slow as well which could result in the arduino not being able to keep up to the character transmissions[/font][/font][/font][/font][/font] [font=OpenSans, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"][font=OpenSans, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"][font=OpenSans, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"][font=OpenSans, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"][font=OpenSans, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"] Instead, write your program to cache/buffer the serial read until a terminator character is sent. Following that, transmit the data in a batch to the lcd.[/font]

[font=OpenSans, -apple-system, BlinkMacSystemFont, Segoe UI, Roboto, Helvetica Neue, Arial, sans-serif, Apple Color Emoji, Segoe UI Emoji, Segoe UI Symbol, Noto Color Emoji]-OR-[/font]

[font=OpenSans, -apple-system, BlinkMacSystemFont, Segoe UI, Roboto, Helvetica Neue, Arial, sans-serif, Apple Color Emoji, Segoe UI Emoji, Segoe UI Symbol, Noto Color Emoji]check to see if there's DMA available on your arduino and read from a DMA buffer[/font]

[font=OpenSans, -apple-system, BlinkMacSystemFont, Segoe UI, Roboto, Helvetica Neue, Arial, sans-serif, Apple Color Emoji, Segoe UI Emoji, Segoe UI Symbol, Noto Color Emoji]-OR-[/font]

[font=OpenSans, -apple-system, BlinkMacSystemFont, Segoe UI, Roboto, Helvetica Neue, Arial, sans-serif, Apple Color Emoji, Segoe UI Emoji, Segoe UI Symbol, Noto Color Emoji]can the arduino have an interrupt execute when a new serial character arrives? If so, do that and add it to a buffer. Then have the main loop read from that buffer[/font][/font]

[font=OpenSans, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"][font=OpenSans, -apple-system, BlinkMacSystemFont, Segoe UI, Roboto, Helvetica Neue, Arial, sans-serif, Apple Color Emoji, Segoe UI Emoji, Segoe UI Symbol, Noto Color Emoji]Either way, that code is skipping/missing characters transmitted from the ez-b. The UART doesn't "wait until a character is received". That's not how serial works. Serial transmits whether the receiver is listening or not - there's no acknowledgement on serial. So by DELAY(100) and LCD.Write(), the Arduino is doing stuff while the EZ-B is transmitting data. This means the arduino is missing bytes because the arduino is busy doing something else instead of receiving data.[/font][/font][/font][/font][/font][/font]

Here - this is a little buffer i wrote for arduino this morning... use something like this.

#define _BUFFER_SIZE 512

byte        _INPUT_BUFFER[_BUFFER_SIZE];
unsigned int _WRITE_POSITION = 0;
unsigned int _READ_POSITION = 0;

bool IsAvail() {

  return _WRITE_POSITION != _READ_POSITION;
}

void serialEvent() {

  while (Serial.available()) {

    _WRITE_POSITION++;

    _INPUT_BUFFER[_WRITE_POSITION % _BUFFER_SIZE] = Serial.read();
  }
}

byte ReadByte() {

  while (_WRITE_POSITION == _READ_POSITION && Serial.available() == 0);

  serialEvent();

  _READ_POSITION++;

  return _INPUT_BUFFER[_READ_POSITION % _BUFFER_SIZE];
}

void loop() {

  if (IsAvail()) {

    byte temp = ReadByte();
    
    if (temp == 48) 
      lcd.clear ();
    else if (temp == 49) 
      lcd.setCursor (0,0);
    else if (temp == 50) 
      lcd.setCursor (0,1);
    else if (temp != 10) 
      lcd.write(temp);
  }
}

Thanks for your response! It's close to midnight in Amsterdam. I will give this a try tomorrow morning. Why is UART1 and UAERT2 working correctly with my code? The corrupted data is only with UART0

That's unusual if that's the case - i would imagine the wire in the UART0 connector is loose. The UART's are hardware on the EZ-B and using high precision timing.

Also, while writing that little bit of code for you, i ended up writing an arduino sketch that pretends to be an EZ-B v4 so ARC can connect to it via USB. The only thing it doesn't do audio or video or hardware UART

Get some rest and try again tomorrow

I replaced the wire (again), used your code but the problem is still there. problem is not that I'm missing characters but UART0 corrupts the characters.

I managed to get a small oscilloscope (BitScope Micro) to work and measured the signals. UART1 and UART2 signal are 3V, UART0 signal is less than 2V